Application health monitoring
Using Oh Dear you can monitor various aspects or your application and server. This way you could get alerts when:
- disk space is running low
- the database is down
- Redis cannot be reached
- mails cannot be sent
- there are many application errors in a small timeframe (via Flare)
- a reboot of your app is required
You can monitor any aspect of your app that you want.
Responding with health check results #
Oh Dear will not run any code inside your application or server. Instead, you should perform the checks yourself. Oh Dear will send an HTTP request to your application to a specific endpoint. Your application should respond with JSON containing the result of health checks.
The request that Oh Dear sends to your app will contain a secret value in the
oh-dear-health-check-secret header. To make sure that a request really comes from Oh Dear, you should verify if the secret value is correct.
Both the endpoint to which the request will be sent and the secret in the header can be specified the application health check settings.
Integration in your application #
Here's how you can let your application respond with health check results in the expected format.
Viewing application health results in Oh Dear #
Oh Dear will check the health results endpoint of your app every few minutes. You can view the results on the application health check screen.
You can click any of the checks to see the history of results for that particular check.
We only store the history for a couple of days. If you need to keep the history longer, consider using our API to fetch the results, and save them on storage of your own.
Getting notified of health check issues #
Whenever a health check problem is detected (or if fixed) Oh Dear can notify you. To do this, you must enable the application health notifications at the site or team level.
For every check that fails, we'll send you a notification. To avoid swamping you in notifications, we'll only send one notification per failing health check per hour. We'll also send you a notification when a problem has been fixed.
Adding and removing health checks #
Any health check result that your server responds with, will be added to Oh Dear. To remove a specific health check from Oh Dear, simply let your server not send the result to us anymore, and we'll remove that check from our system too.